Marks the image for observation by the PerformanceElementTiming API. The value given becomes an identifier for the observed image element. Tümpel also the elementtiming attribute page. Try it Yourself » If a browser cannot find an image, it will display the value of the altbier attribute: The value of the https://jasperqcmwh.blogolenta.com/25657635/the-ultimate-guide-to-image